Creation – the work of creating the world – concluded on Shabbat.
However, although the direct, manifest, and deliberate divine creation came to an end, and since then, the world has operated according to the laws and patterns originally established in it, nevertheless the act of purposive creation never stops.
The task of deliberately rectifying the world by completing the divine creation now devolves upon man.
As it says in the Torah at the end of the Creation, “The heaven and the earth were finished… And God blessed the seventh day and made it holy, because on it He ceased from all His work which God created to do (laasot)” (Gen. 2:1-3).
The Midrash expounds on the last word of the verse, “Everything created during the six days of Creation requires rectification” (Pesikta Rabbati 23).
For God only began the work that He created laasot – in order that it should be perfected by man.
Rabbi Adin Steinsaltz